When I was a teenager, I wanted to be a blood donor.
It didn’t cost anything and I thought it might do some good.
So every few months, I went along and gave a pint.
They gave me a little book and I got a sticker for every visit.
I thought I’d like to give a whole body full of blood – about ten pints.
So I did but, after a few years, when I’d given about 14 pints, I gradually stopped going.
I think I just got bored.
My blood type wasn’t one of the rare ones.
I never heard what happened to it, so I assumed they kept it for a while, then eventually threw it away.
But every so often, I still see advertisements for blood donors.
So they must still need them.
Well, it turns out to be an interesting example of marketing getting it right and getting it wrong.
According to the NHS, in the last ten years, blood donations are down by 40%.
Of course this is a real problem.
Like most clients, the NHS response is to run another recruitment campaign.
In Sweden, they have a different response.
Constantly losing customers (in this case, donors) and replacing them is known as "churn".
There are two ways to handle churn.
The standard reaction is to keep trying to replace the loss.
Concentrate on recruitment.
But the Swedish thought they’d try the opposite way: stop losing them.
So, in Sweden, they use technology to do what people can’t do.
When you give blood, they keep track of each pint.
And immediately after it’s used, they send you a text letting you know when it was used and why.
Whether it’s an accident, or an operation, for an adult, or a child, you know your blood is now in someone else’s veins, saving a life.
This is a great use of social media: wherever you are, whatever you’re doing, you get a text saying your blood has just been used.
And it’s a great use of technology because a human couldn’t keep track of all that blood and send all those messages.
Only an automated system could do that.
And just think how validated that makes donors feel instead of being ignored.
So they won’t get bored and stop donating like I did.
Now think about donations in the UK being down 40% in the last ten years.
If they had concentrated on retention, rather than recruitment, donations would be up to 40% higher than they are now.
Jon Latham of the NHS Blood and Transplant service said: "It’s important to strengthen the donor base."
This is marketing speak for stop losing people.
So instead of running recruitment campaigns that keep trying and failing to replace that 40% churn, they could have concentrated on reducing the rate of churn.
They could have put more effort into retention.
Actually, that’s a great lesson for all marketers.
It’s a lot cheaper, it’s a lot more efficient, to keep the customers you’ve got than just keep trying to recruit new ones.
Of course acquisition is important for growth.
But if acquisition is just replacing loss, it isn’t growth – it’s just churn.
Dave Trott is the author of Creative Mischief, Predatory Thinking and One Plus One Equals Three.